Pane with high-frequency transmission

ABSTRACT

A panel, having at least: at least one first panel having an outer face and an inner face, at least one transparent, electrically-conductive coating, which is arranged on the outer face and/or on the inner face of the first panel, and at least one region having at least one outer de-coated structure and one inner de-coated structure, the transparent, electrically-conductive coating being located between the outer de-coated structure and the inner de-coated structure and inside the inner de-coated structure.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a Continuation Application of Ser. No.14/433,855 filed on Apr. 6, 2015 which, in turn, claims priority to U.S.National Stage of International Application PCT/EP2013/070233 filed onSep. 27, 2013 which, in turn, claims priority to European PatentApplication EP 12188534.7 filed on Oct. 15, 2012, all of which areincorporated herein by reference in their entirety.

BACKGROUND

The invention relates to a pane, in particular a vehicle window pane,with a transparent, electrically conductive coating and low transmissionattenuation for electromagnetic radiation in the high-frequency range.The invention further relates to a method for producing such a pane andits use.

Current motor vehicles require a large number of technical devices forsending and receiving electromagnetic radiation for the operation ofbasic services such as radio reception, preferably in the bands AM, FM,or DAB, mobile telephony in the bands GSM 900 and DCS 1800, UMTS and LTEas well as satellite-supported navigation (GPS) and WLAN.

At the same time, modern vehicle glazings increasingly have all-sidedand full-surface electrically conductive coatings transparent to visiblelight. These transparent, electrically conductive coatings protect, forexample, interiors against overheating due to sunlight or againstcooling, by reflecting incident thermal radiation, as is known from EP378917 A. Transparent, electrically conductive coatings can effecttargeted warming of the pane by application of an electrical voltage, asis known from WO 2010/043598 A1.

Common to the transparent, electrically conductive coatings is the factthat they are also impermeable to electromagnetic radiation in thehigh-frequency range. An all-sided and full-surface glazing of a vehiclewith transparent, electrically conductive coatings renders transmissionand reception of electromagnetic radiation in the interior no longerpossible. For the operation of sensors such as rain sensors, camerasystems, or fixed antennas, one or two localized regions of theelectrically conductive, transparent coating are de-coated. Thesede-coated regions form a so-called communication window or datatransmission window and are known, for example, from EP 1 605 729 A2.

Since the transparent, electrically conductive coatings affect thecoloring and reflectance of a pane, communications windows are visuallyvery conspicuous. Disruptions in the driver's field of view, whichimpair driving safety and which must absolutely be avoided, can resultfrom de-coated regions. Consequently, communication window are arrangedat inconspicuous positions on the pane, for example, in the region ofthe inside rearview mirror of a windshield, and covered by blackimprints and plastic screens.

Such communication windows are too small to enable the transmission andreception of high-frequency electromagnetic radiation, such as isnecessary, for example, for mobile telephony and satellite-supportednavigation. However, the user expects to be able to operate mobiletelephones at any position in the interior of a vehicle.

From EP 0 717 459 A1, US 2003/0080909 A1, and DE 198 17 712 C1, paneswith a metal coating are known, all of which have grid-formed de-coatingof the metal coating. The grid-formed de-coating acts as a low passfilter for incident high-frequency electromagnetic radiation. Thedistances between the grid elements are small compared to the wavelengthof the high-frequency electromagnetic radiation and thus a relativelylarge fraction of the coating is patterned and vision through the paneis relatively greatly impaired. The de-coating of a relatively largefraction of the layer is tedious and cost intensive.

SUMMARY OF INVENTION

The object of the present invention consists in providing a pane with atransparent, electrically conductive coating, which enables adequatetransmission of high-frequency electromagnetic radiation for theoperation of mobile telephony in the bands GSM 900 and DCS 1800, UMTS,and LTE as well as satellite-supported navigation (GPS) and WLAN, whichis visually appealing and does not substantially restrict vision throughthe pane and which can be produced economically. These and other objectsare accomplished according to the proposal of the invention by a panewith the characteristics of the independent claims. Advantageousembodiments of the invention are indicated by the characteristics of thesubclaims.

A method for producing a pane with high-frequency transmission as wellas the use of such a pane are evident from further independent claims.

A pane according to the invention comprises at least one first pane withan outer face and an inner face, at least one transparent, electricallyconductive coating, which is arranged on the outer face and/or the innerface of the first pane and at least one region with at least one outerde-coated structure and one inner de-coated structure, wherein thetransparent, electrically conductive coating is situated between theouter de-coated structure and the inner de-coated structure and insidethe inner de-coated structure.

The present invention is based on the knowledge that a pane according tothe invention with outer and inner de-coated structures has adequatelyhigh permeability for high-frequency electromagnetic radiation. Incontrast to panes according to the prior art, it is unnecessary tode-coat the transparent, electrically conductive coating in large areas.De-coated structures with only a low line width that do notsubstantially impair the vision through the pane and the aestheticappearance of the pane suffice.

The pane according to the invention can be implemented for this assingle pane made of a first pane with a transparent, electricallyconductive coating.

Alternatively, the pane according to the invention can be implemented asa composite pane. A composite pane according to the invention preferablycomprises preferably a first pane, an intermediate layer, and a secondpane as well as at least one transparent, electrically conductivecoating, which is arranged between the intermediate layer and the firstpane and/or between the intermediate layer and the second pane. Thetransparent, electrically conductive coating can also be arranged on acarrier film, which is preferably laminated inside the first and thesecond pane via other intermediate layers.

The first pane and/or the second pane can be, both in the case of thesingle pane and the case of the composite pane, a single pane or analready laminated composite pane made of two or more panes, which form afixedly bonded unit by lamination.

In an advantageous embodiment of the pane according to the invention,the outer de-coated structure and the inner de-coated structure have theshape of a rectangle, a rhombus, a trapezoid, and, in particular, of asquare. Alternatively, the de-coated structures can have the shape of across, an oval, or a circle. With these shapes, it has been possible toobtain particularly high permeabilities for high-frequencyelectromagnetic radiation.

Alternatively, the de-coated structures can have the shape of a hexagon,in particular of a regular hexagon with equally long sides or of anoctagon, in particular of a regular octagon. With these shapes, it hasbeen possible to obtain particularly high permeabilities forhigh-frequency electromagnetic radiation under different polarizationdirections.

In an advantageous embodiment of the pane according to the invention,the outer de-coated structure is completely surrounded by thetransparent, electrically conductive coating. In other words: The outerde-coated structure is completely surrounded on its outer edge by thetransparent electrically conductive coating.

In another advantageous embodiment of the pane according to theinvention, the inner de-coated structure is completely surrounded on itsinner edge by the transparent, electrically conductive coating.

In another advantageous embodiment, the intermediate region between theouter de-coated structure and the inner de-coated structure iscompletely filled with the transparent, electrically conductive coating.The double structure thus created has the particular advantage that highpermeabilities for high-frequency electromagnetic radiation are obtainedwith only a small patterning effort. At the same time, processing timeand processing costs can be kept low.

In an advantageous embodiment of the pane according to the invention,the distance b between the de-coated structures is from 0.5 mm to 30 mm,preferably from 1 mm to 5 mm. With this distance b, it was possible toobserve particularly low transmission attenuations for high-frequencyelectromagnetic radiation. Needless to say, the optimal distance bdepends on the frequency of the high-frequency electromagnetic radiationfor which the transmission through the pane is optimized. This can bedetermined by simple simulations.

The outer de-coated structure and the inner de-coated structure have, inparticular, the same shape. In a particularly advantageous embodiment,the outer de-coated structure and the inner de-coated structure arearranged concentrically to one another. In other words: The twode-coated structures have a common center and, with the same shape, aconstant distance between the de-coated lines of the structure.

In another advantageous embodiment of a pane according to the invention,a plurality of de-coated structures with different shapes are arrangedon a pane. This has the particular advantage that a greater bandwidthfor multiple frequency ranges and different polarization can beobtained.

In another advantageous embodiment, the inner region of the innerde-coated structure is completely filled with the transparent,electrically conductive coating or merely has one or a plurality ofother double structures consisting of other smaller, outer de-coatedstructures and other smaller, inner de-coated structures. This makes itpossible to obtain particularly high permeabilities for high-frequencyelectromagnetic radiation with only a small patterning effort. At thesame time, processing time and processing costs can be kept low.

In another advantageous embodiment of a pane according to the invention,the outer de-coated structure and the inner de-coated structure areconnected to each other via at least one additional de-coated line andpreferably via 2 to 100 additional de-coated lines. The additionalde-coated line is preferably rectilinearly and/or orthogonally arrangedto the de-coated structures. The distance between the lines ispreferably less than one fourth of the wavelength λ of thehigh-frequency electromagnetic radiation and particularly preferablyfrom λ/20 to λ/500. Alternatively, the additional de-coated line canhave a curved course and, for example, a sinusoidal course. Theadditional de-coated lines have the particular advantage that fewerdisruptive field-induced currents can form between the outer de-coatedstructure 4.1 and the inner de-coated structure 4.2. Thus, particularlyhigh permeabilities for high-frequency electromagnetic radiation can beobtained. In a particularly advantageous embodiment, the area of theadditional de-coated lines between the outer de-coated structure and theinner de-coated structure is from 0.1% to 25% and preferably from 1% to5% of the area of the intermediate region between the outer de-coatedstructure and the inner de-coated structure. Thus, high permeabilitiesfor high-frequency electromagnetic radiation can be obtained with only asmall patterning effort. At the same time, processing time andprocessing costs can be kept low.

In another advantageous embodiment, the de-coated structures accordingto the invention have a line width d from 0.025 mm to 0.3 mm andpreferably from 0.03 mm to 0.14 mm. Such line widths are technicallysimple to produce, for example, by laser patterning. Furthermore, theyhardly impair the optical vision through the pane.

The transparent, electrically conductive coating comprises at least oneregion with de-coated structures, preferably at least four regions andparticularly preferably 10 to 50 regions. The regions are preferablyarranged horizontally and/or vertically. A slight deviation from thehorizontal and/or vertical arrangement can result from the fact that thecoated structures in the transparent, electrically conductive coatingare de-coated on a flat pane and the pane with the de-coated structuresis then bent. With such a distribution of the de-coated lines,particularly low transmission attenuation and favorable distribution ofthe reception and transmission power behind the pane can be obtained. Aregion with horizontally and/or vertically arranged de-coated structurescan also have, in its entirety, an angle α relative to the horizontal,for example, from 10° to 80° and preferably from 30° to 50°.

The area fraction of the regions that comprise the de-coated structuresand the intermediate spaces directly adjacent de-coated structures isadvantageously from 7% to 25% of the total area of the pane. With thisarea fraction, particularly low transmission attenuation and favorabledistribution of the reception and transmission power behind the pane canbe obtained. At the same time, there is a favorable correlation of theimprovement of the transmission to the processing costs for thede-coating.

The number of regions and de-coated structures is governed by therequirements for transmission attenuation and the dimensions of thepane. In the case of a windshield, the size and configuration of theinterior space in particular must be taken into account.

In an advantageous embodiment of the invention as a windshield, theregions are arranged with the de-coated structures outside the A-fieldof view of the driver. The A-field of view of the driver is defined, forexample, in accordance with Annex 18 ECE R43. Although the line widthsof the de-coated structures according to the invention are very thinand, consequently, visually inconspicuous, it is considered imperativeto avoid any disruption in the field of view of the driver.

In an advantageous embodiment of the invention, the minimum distance hbetween two adjacent regions with de-coated structures is from 1 mm to100 mm, preferably from 1 mm to 10 mm and particularly preferably from 2mm to 6 mm. The minimum distance h depends in particular on thefrequency for which the pane is intended to have optimum transmission.The minimum distance h is preferably the horizontal or vertical minimumdistance between two adjacent regions. For minimum distances h of lessthan 1 mm, a strong coupling between the de-coated structures thatresults in an undesirable increase in transmission attenuation canoccur.

The length l of the de-coated structures and in particular of themaximum length of the outer de-coated structure is preferably from 10 mmto 150 mm. The length l is adapted to the frequency band or thefrequency bands for which the pane is to have the least possibletransmission attenuation. Furthermore, the length l depends on thewavelength of the high-frequency electromagnetic radiation, the sheetresistance of the transparent, electrically conductive coating, and theeffective relative permittivity ε_(eff) of the panes and of theintermediate layer.

For mobile telephony operation in the GSM 900 band, the length l ispreferably from 35 mm to 120 mm and particularly preferably from 40 mmto 60 mm. In the region of 1.8 GHz, the length l with low transmissionattenuation is preferably from 15 mm to 35 mm. The optimal length l withlow transmission attenuation with adequate bandwidth can be determinedby the person skilled in the art in the context of simple simulationsand experiments.

In another preferred embodiment, the length l of the de-coatedstructures and in particular the maximum length of the outer de-coatedstructure, disregarding the sheet resistance, is from λ/(7*√{square rootover (ε_(eff))}) to (3*λ)/(2*√{square root over (_(eff))}), where λindicates the wavelength for which the transmission is intended to beoptimized. The length l is preferably roughly λ(4*√{square root over(ε_(eff))}). As investigations of the inventor revealed, structures withlengths l in this range have low transmission attenuation with adequatebandwidth.

In an advantageous embodiment of the pane according to the invention,b/l≤⅕, where b is the distance between the outer de-coated structure andthe inner de-coated structure. As investigations of the inventorrevealed, such ratios between the distance b and the length l delivergood and adequate bandwidth in the transmission through the paneaccording to the invention in the required wavelength range for whichthe transmission had been optimized.

The sides of the de-coated structures are arranged, in the case ofrectangular, square, or trapezoidal shapes, preferably horizontally orvertically, in particular with regard to the arrangement in theinstalled state of the pane at its point of use. Horizontally runninglines of the de-coated structures are particularly advantageous in theinstalled position since they are visually less disruptive and causeless scattered light and reflections than non-horizontally ornon-vertically running lines.

In an advantageous embodiment of the pane according to the invention, atleast one other outer de-coated structure is arranged inside a firstinner de-coated structure and one other inner de-coated structure isarranged inside the other outer de-coated structure. The other de-coatedstructures preferably have the same shape and are preferably arrangedone over another and concentrically relative to the first de-coatedstructures. Needless to say, the other de-coated structures can alsohave different shapes or their center can be arranged offset. Thedistance between the first outer de-coated structure and the first innerde-coated structure is preferably equal to the distance between theother outer de-coated structure and the other inner de-coated structure.Needless to say, the distances need not be equal. Due to the differentlengths of the outer de-coated structures arranged nestled in eachother, such panes according to the invention have improved transmissionfor a plurality of frequency ranges.

The pane preferably contains glass, particularly preferably flat glass,float glass, quartz glass, borosilicate glass, soda lime glass, or clearplastics, preferably rigid clear plastics, in particular polyethylene,polypropylene, polycarbonate, polymethyl methacrylate, polystyrene,polyamide, polyesters, polyvinyl chloride, and/or mixtures thereof.Suitable types of glass are known, for example, from EP 0 847 965 B1.

The thickness of the pane can vary widely and thus be ideally adapted tothe requirements of the individual case. Preferably, panes with thestandard thicknesses from 1.0 mm to 25 mm and preferably from 1.4 mm to2.1 mm are used. The size of the pane can vary widely and is governed bythe size of the application according to the invention.

In an advantageous embodiment of the invention, the pane has dielectricproperties and a relative permittivity from 2 to 8. A pane made ofpolymers preferably has a relative permittivity from 2 to 5. A pane madeof glass preferably has a relative permittivity from 6 to 8 and inparticular of roughly 7.

The pane can have any three-dimensional shape. Preferably, thethree-dimensional shape has no shadow zones such that it can, forexample, be coated by cathodic sputtering. Preferably, the pane isplanar or slightly or greatly curved in one or more spatial directions.The pane can be colorless or colored.

In a preferred embodiment of the pane according to the invention as acomposite pane, at least one of the panes contains glass and at leastone of the panes contains plastic. In particular, in the case of a useaccording to the invention as a vehicle window pane, the outer panecontains glass and the inner pane contains plastic.

The panes of the composite pane are bonded to each other via at leastone intermediate layer. The intermediate layer preferably contains athermoplastic polymer, such as polyvinyl butyral (PVB), ethylene vinylacetate (EVA), polyurethane (PU), polyethylene terephthalate (PET), or aplurality of layers thereof, preferably with thicknesses from 0.3 mm to0.9 mm.

The transparent, electrically conductive coating according to theinvention is permeable for electromagnetic radiation, preferablyelectromagnetic radiation of a wavelength from 300 to 1,300 nm, inparticular for visible light. “Permeable” means that the totaltransmission of the composite pane complies with the legal requirementsfor windshields and front side windows and is permeable in particularfor visible light preferably >70% and in particular >75%. For rear sidewindows and rear windows “permeable” can also mean 10% to 70% lighttransmission.

The transparent, electrically conductive coating is preferably afunctional coating, particularly preferably a functional coating withanti-sunlight protection. A coating with anti-sunlight protection hasreflecting properties in the infrared range and thus in the range ofsunlight. Thus, the heating of the interior of a vehicle or building asa result of sunlight is advantageously reduced. Such coatings are knownto the person skilled in the art and typically contain at least onemetal, in particular silver or a silver-containing alloy. Thetransparent, electrically conductive coating can include a sequence of aplurality of individual layers, in particular at least one metal layerand dielectric layers that include, for example, at least one metaloxide. The metal oxide preferably contains zinc oxide, tin oxide, indiumoxide, titanium oxide, silicon oxide, aluminum oxide, or the like, aswell as combinations of one or a plurality thereof. The dielectricmaterial can also contain silicon nitride, silicon carbide, or aluminumnitride.

This layer structure is generally obtained by a sequence of depositionprocedures that are performed by a vacuum method, such as magnetic fieldassisted cathodic sputtering. Very fine metal layers, which contain, inparticular, titanium or niobium, can also be provided on both sides ofthe silver layer. The lower metal layer serves as an adhesion andcrystallization layer. The upper metal layer serves as a protective andgetter layer to prevent a change in the silver during the other processsteps.

Particularly suitable transparent, electrically conductive coatingsinclude at least one metal, preferably silver, nickel, chromium,niobium, tin, titanium, copper, palladium, zinc, gold, cadmium,aluminum, silicon, tungsten or alloys thereof, and/or at least one metaloxide layer, preferably tin-doped indium oxide (ITO), aluminum-dopedzinc oxide (AZO), fluorine-doped tin oxide (FTO, SnO₂:F), antimony-dopedtin oxide (ATO, SnO₂:Sb), and/or carbon nanotubes and/or opticallytransparent, electrically conductive polymers, preferablypoly(3,4-ethylenedioxythiophenes), polystyrene sulfonate,poly(4,4-dioctylcylopentadithiophen),2,3-dichloro-5,6-dicyano-1,4-benzoquinone, mixtures and/or copolymersthereof.

The thickness of the transparent, electrically conductive coating canvary widely and can be adapted to the requirements of the individualcase. It is essential that the thickness of the transparent,electrically conductive coating not be so great that it becomesimpermeable for electromagnetic radiation, preferably electromagneticradiation of a wavelength from 300 to 1.300 nm and in particular visiblelight. The transparent, electrically conductive coating preferably has alayer thickness from 10 nm to 5 μm and particularly preferably from 30nm to 1 μm.

The sheet resistance of the transparent, electrically conductive coatingis preferably from 0.35 ohm/square to 200 ohm/square, preferably 0.5ohm/square to 200 ohm/square, most particularly preferably from 0.6ohm/square to 30 ohm/square, and, in particular, from 2 ohm/square to 20ohm/square. The transparent, electrically conductive coating can, inprinciple, have even lower sheet resistances than 0.35 ohm/square, inparticular if, in its use, only a low light transmission is required.The transparent, electrically conductive coating preferably has goodinfrared reflecting properties and/or particularly low emissivity(low-E).

In an advantageous embodiment of the composite pane according to theinvention, at least one transparent, electrically conductive layer issituated on at least one of the inner sides of the panes. In the case ofa pane composite made of two panes, a transparent, electricallyconductive layer can be situated on the inner side of one or the otherpanes. Alternatively, a transparent, electrically conductive layer can,in each case, be situated on each of the two inner sides. In the case ofa pane composite made of more than two panes, multiple transparent,electrically conductive coatings can also be situated on multiple innersides of the panes. In that case, the regions with de-coated structuresare preferably arranged congruently in the different coatings in orderto ensure low transmission attenuation.

Alternatively, a transparent, electrically conductive coating can beembedded between two thermoplastic intermediate layers. In that case,the transparent, electrically conductive coating is preferably appliedon a carrier film or carrier pane. The carrier film or carrier panepreferably contains a polymer, in particular polyvinyl butyral (PVB),ethylene vinyl acetate (EVA), polyurethane (PU), polyethyleneterephthalate (PET), or combinations thereof.

In an alternative embodiment of the invention, the transparent,electrically conductive layer or a carrier film with the transparent,electrically conductive layer is arranged on one side of a single pane.

The invention includes a method for producing a pane according to theinvention as described above, wherein at least:

-   (a) the transparent, electrically conductive coating is applied on    the outer face and/or the inner face of a first pane, and-   (b) at least one region with at least one outer de-coated structure    and one inner de-coated structure is introduced into the    transparent, electrically conductive coating, wherein the    transparent, electrically conductive coating is situated between the    outer de-coated structure and the inner de-coated structure and    inside the inner de-coated structure.

In an alternative embodiment of the method according to the invention,the transparent, electrically conductive coating can be applied on acarrier film, for example, a PET film. The carrier film can be bonded tothe first pane directly or via at least one intermediate layer. Theregion with the de-coated structures can be introduced into thetransparent, electrically conductive coating before or after the bondingto the first pane.

The application of the transparent, electrically conductive coating inprocess step (a) can be done using methods known per se, preferably bymagnetic field assisted cathodic sputtering. This is particularlyadvantageous with regard to simple, rapid, economical, and uniformcoating of the first pane. The transparent, electrically conductivecoating can, however, also be applied, for example, by vapor deposition,chemical vapor deposition (CVD), plasma enhanced chemical vapordeposition (PECVD), or by wet chemical methods.

The first pane can be subjected to a temperature treatment after processstep (a). The first pane with the electrically conductive coating isheated to a temperature of at least 200° C., preferably at least 300° C.The temperature treatment can serve to increase transmission and/or toreduce the sheet resistance of the transparent, electrically conductivecoating.

The first pane can be bent after process step (a), typically at atemperature from 500° C. to 700° C. Since it is technically simpler tocoat a flat pane, this approach is advantageous when the first pane isto be bent. Alternatively, the first pane can, however, also be bentbefore process step (a), for example, if the transparent, electricallyconductive coating is unsuitable to withstand a bending process withoutdamage.

The de-coating of the de-coated structures in the transparent,electrically conductive coating is preferably done by a laser beam.Methods for patterning thin metal films are known, for example, from EP2 200 097 A1 or EP 2 139 049 A1. The width of the de-coating ispreferably 10 μm to 1000 μm, particularly preferably 25 μm to 300 μm,and in particular 70 μm to 140 μm. In this range, a particularly cleanand residue-free de-coating takes place using the laser beam. Thede-coating by means of laser beam is particularly advantageous since thede-coated lines are optically very unobtrusive and the appearance andthe vision through the pane is impaired only a little. The de-coating ofa line of the width d, which is wider than a laser cut, is done bymultiple passes of the line with the laser beam. Consequently, processduration and process costs rise with an increasing line width.Alternatively, the de-coating can be done by mechanical removal as wellas by chemical or physical etching.

An advantageous improvement of the method according to the inventionincludes at least the following additional steps:

-   (c) Arranging a thermoplastic intermediate layer on the first pane    and arranging a second pane on the thermoplastic intermediate layer,    and-   (d) Bonding the first pane and the second pane via the thermoplastic    intermediate layer.

In process step (c), the first pane is advantageously arranged such thatthe one of its surfaces that is provided with the electricallyconductive coating faces the intermediate layer. This has the particularadvantage that the transparent, electrically conductive coating isprotected against environmental influences and against touching by theuser by lamination.

The thermoplastic intermediate layer can be implemented by a singlethermoplastic film or even by two or more thermoplastic films that arearranged congruently one over another.

The bonding of the first and second pane in process step (d) ispreferably done under the action of heat, vacuum, and/or pressure.Methods known per se for producing a pane can be used.

For example, so-called autoclave methods can be performed at an elevatedpressure of roughly 10 bar to 15 bar and temperatures from 130° C. to145° C. over roughly 2 hours. Vacuum bag or vacuum ring methods knownper se operate, for example, at roughly 200 mbar and 80° C. to 110° C.The first pane, the thermoplastic intermediate layer, and the secondpane can also be pressed in a calender between at least one pair ofrollers to form a composite pane. Facilities of this type for producingcomposite panes are known and usually have at least one heating tunnelupstream from a pressing system. During the pressing procedure, thetemperature is, for example, from 40° C. to 150° C. Combinations ofcalender and autoclave methods have proved particularly effective inpractice. Alternatively, vacuum laminators can be used. These consist ofone or a plurality of heatable and evacuable chambers in which the firstpane and the second pane can be laminated within, for example, roughly60 minutes at reduced pressures from 0.01 mbar to 800 mbar andtemperatures from 80° C. to 170° C.

To produce a bent composite pane, the first pane and the second pane canbe bent, before the process step (c), in a hot bending process known perse. The first and the second pane can advantageously be bent togethersuch that the same curvature of the panes is ensured.

The invention further extends to the use of a pane as described above ina vehicle body or in a vehicle door of a means of transportation onland, on water, or in the air, in buildings as part of an externalfaçade or as building windows and/or as a built-in part in furniture andappliances.

The use of a pane according to the invention as a windshield isparticularly advantageous. Mobile phone base stations are, for example,installed along highways or expressways. The high-frequency,electromagnetic radiation can then arrive in the driving direction fromthe front through the windshield according to the invention into theinterior of the motor vehicle. In cities, the mobile phone base stationsare customarily installed on roofs or elevated positions and beam downfrom above. Satellite navigation signals likewise beam down from aboveto a vehicle. Since, to improve aerodynamics, windshields have a sharplyinclined installed position, mobile phone signals or satellitenavigation signals can also enter the vehicle interior from abovethrough the pane.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is explained in detail in the following with reference todrawings and an example. The drawings are not completely true to scale.The invention is in no way restricted by the drawings. They depict:

FIG. 1 a schematic representation of a pane according to the inventionin plan view,

FIG. 2 a schematic representation einer pane according to the prior artin plan view,

FIG. 3A a schematic representation einer pane according to the inventionin plan view,

FIG. 3B a cross-sectional representation along the section line A-A′ ofFIG. 3A,

FIG. 3C an enlarged representation of the detail Y of the pane accordingto the invention of FIG. 3A,

FIG. 3D an enlarged representation of the detail Z of the pane accordingto the invention of FIG. 3C,

FIG. 4 a cross-sectional representation along the section line A-A′ ofFIG. 3A of an alternative exemplary embodiment of a pane according tothe invention,

FIG. 5 a cross-sectional representation along the section line A-A′ ofFIG. 3A of an alternative exemplary embodiment of the pane according tothe invention,

FIG. 6 a schematic representation of an alternative exemplary embodimentof a pane according to the invention in plan view,

FIG. 7 an enlarged representation of the detail Z of an alternativeexemplary embodiment of a pane according to the invention of FIG. 3C,

FIG. 8 an enlarged representation of the detail Z of an alternativeexemplary embodiment of a pane according to the invention of FIG. 3C,

FIG. 9 an enlarged representation of the detail Z of an alternativeexemplary embodiment of a pane according to the invention of FIG. 3C,

FIG. 10 an enlarged representation of the detail Z of an alternativeexemplary embodiment of a pane according to the invention of FIG. 3C,

FIG. 11 an enlarged representation of the detail Z of an alternativeexemplary embodiment of a pane according to the invention of FIG. 3C,

FIG. 12A an enlarged representation of the detail Y of an alternativeexemplary embodiment of a pane according to the invention of FIG. 3A,

FIG. 12B an enlarged representation of the detail Z of the paneaccording to the invention of FIG. 11,

FIG. 13 an enlarged representation of the detail Y of an alternativeexemplary embodiment of a pane according to the invention of FIG. 3A,

FIG. 14 an enlarged representation of the detail Z of an alternativeexemplary embodiment of a pane according to the invention of FIG. 3A,

FIG. 15 an enlarged representation of the detail Y of an alternativeexemplary embodiment of a pane according to the invention of FIG. 3A,

FIG. 16A a flowchart of an exemplary embodiment of the method accordingto the invention,

FIG. 16B a flowchart of an exemplary embodiment of the method accordingto the invention,

FIG. 17 a diagram of the transmission attenuation as a function of thedistance h between the regions,

FIG. 18 a diagram of the transmission attenuation as a function of thedistance b between the outer and inner de-coated structure,

FIG. 19 a diagram of the transmission attenuation for various exemplaryembodiments,

FIG. 20 a diagram of the transmission attenuation for an alternativeexemplary embodiment of a pane according to the invention,

FIG. 21 a schematic representation of a detail of an alternative paneaccording to the invention in plan view, and

FIG. 22 a diagram of the transmission attenuation for the exemplaryembodiment of a pane according to the invention in accordance with FIG.21.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 depicts a schematic representation of a pane according to theinvention 10. The pane 10 comprises a first pane 1.1 on whose outer faceIII a transparent electrically conductive coating 3 is arranged. Thetransparent, electrically conductive coating 3 has a rectangular region9. The region 9 is defined by the outer shape of an outer de-coatedstructure 4.1. Along the outer de-coated structure 4.1, there is notransparent, electrically conductive coating 3 or the transparent,electrically conductive coating 3 has been removed, for example, bylaser patterning. A likewise rectangular inner de-coated structure 4.2is arranged inside the outer de-coated structure 4.1. Along the innerde-coated structure 4.2, there is no transparent, electricallyconductive coating 3 or the transparent, electrically conductive coating3 has been removed, for example, by laser patterning. The outerde-coated structure 4.1 is completely surrounded by the transparent,electrically conductive coating 3. Furthermore, a part of thetransparent, electrically conductive coating 3 is arranged between theouter de-coated structure 4.1 and the inner de-coated structure 4.2 aswell as inside the inner de-coated structure 4.2. In the presentexample, the intermediate region between the outer de-coated structure4.1 and the inner de-coated structure 4.2 as well as the inner region ofthe inner de-coated structure 4.2 are completely filled with thetransparent, electrically conductive coating 3. By means of the outerde-coated structure 4.1 and the inner de-coated structure 4.2, thetransparent, electrically conductive coating 3, otherwise impermeablefor high-frequency electromagnetic radiation becomes permeable. Thede-coated structures 4.1, 4.2 are, for example, de-coated by laserpatterning and have only a very small line width of, for example, 0.1mm. The view through the pane according to the invention 10 is notsignificantly impaired and the de-coated structures 4.1, 4.2 are hardlydiscernible.

FIG. 2 depicts a schematic representation of a pane 12 according to theprior art. The pane 12 comprises, like the pane 10 of FIG. 1, a firstpane 1.1 on whose outer face III a transparent, elektromagnetischecoating 3 is arranged. In order to make the pane 12 permeable forhigh-frequency electromagnetic radiation, the transparent,electromagnetic coating 3 has a rectangular de-coated region 4. Incontrast to the pane according to the invention 10 of FIG. 1, the areaof the de-coated region 4 is very large and the de-coating is clearlydiscernible on the pane 12. Vision through such a pane 12 is impairedand the pane is, for example, not suitable as a pane in a vehicle.

FIG. 3A depicts a schematic representation of a pane 10 according to theinvention using the example of a vehicle windshield in plan view. FIG.3B depicts a cross-sectional representation along the section line A-A′of FIG. 3A using the example of a composite pane. FIG. 3C depicts anenlarged detail Y of FIG. 3A; and FIG. 3D, an enlarged detail Z of FIG.3C. The pane 10 is, without restricting the invention, optimized for thetransmission of mobile phone radiation in the GSM 900 band. The pane 10comprises a composite pane 1 made of two individual panes, namely, arigid first pane 1.1 and a rigid second pane 1.2, which are fixedlybonded to each other via a thermoplastic intermediate layer 2. Theindividual panes 1.1,1.2 have roughly the same size and aremanufactured, for example, of glass, in particular float glass, castglass, and ceramic glass, being equally possibly produced from anonglass material, for example, plastic, in particular polystyrene (PS),polyamide (PA), polyester (PE), polyvinyl chloride (PVC), polycarbonate(PC), polymethyl methacrylate (PMA), or polyethylene terephthalate(PET). In general, any material with adequate transparency, sufficientchemical resistance, as well as suitable shape and size stability can beused. For another type of use, for example, as a decorative part, itwould also be possible to produce the first pane 1.1 and the second pane1.2 from a flexible and/or a non-transparent material. The respectivethickness of the first pane 1.1 and of the second pane 1.2 can varywidely depending on the use and can be, in the case of glass, forexample, in the range from 1 to 24 mm. In the present example, the firstpane 1.1 has a thickness of 2.1 mm; and the second pane 1.2, a thicknessof 1.8 mm.

The pane faces are identified with the Roman numerals I-IV, where face Icorresponds to the outer face of the second pane 1.2, face II to theinner face of the second pane 1.1, face III to the outer face of thefirst pane 1.1, and face IV to the inner face of the first pane 1.1 ofthe composite pane 1. In the context of the present invention, “outerface” is the face of a pane that faces the exterior of the vehicle.“Inner face” is the face of a pane that faces the interior of thevehicle. In the use as a windshield, the face I faces the externalenvironment and the face IV faces the passenger compartment of the motorvehicle. Needless to say, the face IV can also face outward and the faceI can face the passenger compartment of the motor vehicle.

The intermediate layer 2 for the bonding of the first pane 1.1 and thesecond pane 1.2 preferably contains an adhesive plastic preferably basedon polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), orpolyurethane (PU).

The composite pane 1 is transparent to visible light, for example, inthe wavelength range from 350 nm to 800 nm, with the term “transparency”understood to mean light permeability of more than 50%, preferably morethan 70%, and in particular preferably more than 75%.

The relative permittivity of the panes 1.1,1.2 of the composite pane 1is, for panes made of float glass, from 6 to 8 and, for example, 7.

In the example presented, the transparent, electrically conductivecoating 3 is applied on the face III of the inner first pane 1.1 facingthe intermediate layer 2. The transparent, electrically conductivecoating 3 serves, for example, as an infrared reflecting layer of thecomposite pane 1. This means that the fraction of thermal radiation ofincident sunlight is largely reflected. With the use of the compositepane 1 in a vehicle, this provides for reduced heating of the interiorin sunlight. The transparent, electrically conductive coating 3 isknown, for example, from EP 0 847 965 B1 and includes two silver layersthat are embedded in each case between a plurality of metal and metaloxide layers. The transparent, electrically conductive coating 3 has asheet resistance of roughly 4 ohm/square. The transparent, electricallyconductive coating 3 can also serve as an electrically heatable coatingand can be contacted by means of bus bars known per se and can beconnected to a voltage source.

The transparent, electrically conductive coating 3 can, however, bearranged on the face II of the outer, second pane 1.2 facing thethermoplastic intermediate layer 2, or on the two interior pane faces IIand III. The transparent, electrically conductive coating 3 can bearranged additionally or exclusively on one of the outer faces I and IVof the composite pane 1.

The transparent, electrically conductive coating 3 is applied on theentire first pane 1.1, minus an edge-de-coated region 5. The edgede-coating in the region 5 prevents a contact of the transparent,electrically conductive coating 3, which is advantageous withcorrosion-sensitive coatings. Moreover, the second pane 1.2 is provided,for example, with an opaque ink layer that is applied on the face II andforms a frame-like peripheral masking strip, which is not shown indetail in the figures. The ink layer consists, preferably, of anelectrically nonconductive black-colored material, which can be firedinto the first pane 1.1 or the second pane 1.2. The masking stripprevents, on the one hand, seeing an adhesive strand with which thecomposite pane 1 is glued into the vehicle body; on the other, it servesas UV protection for the adhesive material used.

Furthermore, the transparent, electrically conductive coating 3 ispartially de-coated in a plurality of regions 9. In the examplepresented of FIG. 3A, in each case, two rows of 12 regions 9 each arearranged almost vertically one over the other. The 24 regions 9 arearranged horizontally next to each other in a section 11 on the top edgeof the pane 1. The terms “vertical” and “horizontal” indicate theposition in the installed position of the motor vehicle window pane. The24 regions 9 are arranged on the top pane edge of the longer side of thepane 1 and outside the A-field of view 7 of the driver in accordancewith Annex 18 of the ECE R43.

Two rows of 12 regions 9 each arranged vertically one above the otherwith de-coated structures 4.1, 4.2 are arranged on the upper edge of thepane 10. The area of the 24 regions 9 covers roughly 7% of the entirearea of the composite pane 1. This area fraction yields a particularlyfavorable relationship between process costs, visual aspect, andtransmission. The horizontal and vertical distance h between the tworegions 9 is, for example, 2 mm.

FIG. 3C depicts an enlarged detail Y of FIG. 3A with eight regions 9,and FIG. 3D depicts an enlarged detail Z of FIG. 3C. Each region 9includes an outer de-coated structure 4.1 and an inner de-coatedstructure 4.2 with a square shape. The upper and lower sides of thequadratic shape are arranged horizontal to the installation direction.This horizontal orientation is particularly advantageous for receptionof vertically transmitted mobile telephony. The invention also includesde-coated structures 4.1,4.2 arranged at different angles if this isexpedient.

The line width d of the de-coating of the de-coated structures 4.1,4.2is constant and is, for example, 100 μm. Such small line widths arehardly perceptible visually to the eye and do not impair vision throughthe pane 10 such that the pane 10 is suitable for use as a windshield ofa vehicle.

The distance distance b from the outer de-coated structure 4.1 to theinner de-coated structure 4.2 is, for example, 1 mm both in the verticaldirection (b_(v)) and in the horizontal direction (b_(h)). Needless tosay, the distances b_(v) and b_(h) need not be equal. The outerde-coated structure 4.1 determines the dimensions of the region 9 and inparticular the length l of the region. In the example presented, theouter de-coated structure 4.1 has a length l of, for example, 42 mm. Thedistance b affects, in particular, the bandwidth and the level of thetransmission permeability for high-frequency electromagnetic radiation.

The length l is tuned to the high-frequency electromagnetic radiationwith frequency f, for which the pane 10 is intended to be maximallypermeable. The length l depends, for de-coated structures with a squareshape, in a first approximation using the equationI=c/(4*f(ε_(eff))^(0.5)), on the effective relative permittivity ε_(eff)of the pane 1.1,1.2 and of the intermediate layer 2, where c is thespeed of light. Due to adjacently arranged regions 9 with de-coatedstructures 4.1,4.2, there can be influencing of the regions 9 among eachother and thus the formation of resonances and frequency shifts thatnecessitate adaptation and optimization of the length l, of the width b,of the vertical distance d, and of the horizontal distance h. These canbe calculated using simulations familiar to the person skilled in theart.

The pane 10 of FIG. 3A was optimized for the operation of the mobiletelephony band GSM 900. By variation of the parameters, such as thelength l of the de-coated regions, the pane 10 can, in a simple manner,be optimized for the transmission of other frequency bands for aplurality of frequency bands.

FIG. 4 depicts a cross-sectional representation along the section lineA-A′ of FIG. 3A of an exemplary embodiment of a pane according to theinvention 10 with a composite pane 1. In this exemplary embodiment, thefirst pane 1.1 and the second pane 1.2 are bonded to a three-plyintermediate layer. The three-layer intermediate layer includes a film6, which contains, for example, polyethylene terephthalate (PET), andwhich is arranged between two layers 2 of an adhesive plastic, forexample, polyvinyl butyral (PVB). The PET film is implemented here, forexample, as a carrier of the transparent, electrically conductivecoating 3.

FIG. 5 depicts a cross-sectional representation along the section lineA-A′ of FIG. 3A of an exemplary embodiment of a pane according to theinvention 10 mit a single pane 1′. The transparent, electricallyconductive coating 3 with the regions 9 with de-coated structures4.1,4.2 is arranged on the inner face IV of the single plane 1′ facingthe vehicle interior. The shape and material of the single pane 1′correspond to the first pane 1.1 of FIG. 3A. The transparent,electrically conductive coating 3 and the regions 9 also correspond tothe exemplary embodiment of FIG. 3A. The transparent, electricallyconductive coating 3 here is, for example, a so-called low-E layer andhas low emissivity for infrared radiation. The transparent, electricallyconductive coating 3 contains or is made of, for example, an indium tinoxide (ITO) layer with a sheet resistance of 20 ohm/square. The indiumtin oxide layer is implemented inert relative to environmentalinfluences and scratch resistant such that the indium tin oxide layercan be arranged on the surface of a side window of a motor vehiclefacing a vehicle interior.

Alternatively, a scratch and corrosion-sensitive or an electrically liveheatable transparent, electrically conductive coating 3 can be protectedby an insulating layer that contains, for example, a polymer film, suchas polyethylene terephthalate (PET) or polyvinyl fluoride (PVF).Alternatively, the transparent, electrically conductive coating 3 canhave an insulating and scratch resistant cover layer made of inorganicoxides, such as silicon oxide, titanium oxide, tantalum pentoxide, orcombinations thereof.

FIG. 6 depicts a schematic representation of an alternative exemplaryembodiment of a pane according to the invention 10 in plan view. Incontrast to FIG. 3A, further regions 9 are arranged on the side edgesand on the lower edge of the pane 10. By means of the further regions 9,the permeability for electromagnetic radiation according to theinvention inside the motor vehicle interior can be increased. Animprovement of the permeability can be obtained in particular on thelower edge of the pane 10 and thus the reception and transmission powerof sensors, for example, GPS sensors that are installed in theinstrument panel can be improved. An arrangement 13 of, for example,nine regions 9 arranged horizontally and vertically to each other isarranged on the lower edge of the pane. The arrangement 13 has an angleα of, for example, 45° relative to the lower edge of the pane 10 andthus to the horizontal in the installed position of the pane 10. Thearrangement 13 of the regions 9 in a horizontal and vertical positionrelative to each other results in particularly high transmission throughthis region of the pane 10.

FIG. 7 depicts an enlarged representation of the detail Z of analternative exemplary embodiment of a pane according to the invention ofFIG. 3D. In contrast to FIG. 3D, the outer structure 4.1 and the innerstructure 4.2 are connected by four de-coated lines 8 per side. Thede-coated lines 8 are arranged orthogonal to the side lines of the outerstructure 4.1 and of the inner structure 4.2. The de-coated lines 8have, for example, a line width d of 0.1 mm, which corresponds to theline width d of the de-coated structures 4.1,4.2. The distance betweenthe lines 8 should be less than one fourth the wavelength λ, of thehigh-frequency electromagnetic radiation and preferably from λ/20 toλ/500 such that few disruptive field-induced currents can be formedbetween the outer de-coated structure 4.1 and the inner de-coatedstructure 4.2. By means of the de-coated lines 8, the transmissionattenuation of the high-frequency electromagnetic radiation is clearlyreduced and, at the same time, the outlay for the laser processing ofthe transparent, electrically conductive coating 3 is only slightlyincreased.

FIG. 8 depicts an enlarged representation of the detail Z of analternative exemplary embodiment of a pane 10 according to the inventionof FIG. 3D. In contrast to FIG. 5, the outer structure 4.1 and the innerstructure 4.2 are connected via nine de-coated lines 8 per side. Thus,the transmission properties are further improved compared to a pane 10in accordance with FIG. 7, in other words, in particular, thetransmission attenuation decreases.

FIG. 9 depicts an enlarged representation of the detail Z of analternative exemplary embodiment of a pane 10 according to the inventionof FIG. 3D. In contrast to FIG. 8, the complete region 4 between theouter structure 4.1 and the inner structure 4.2 is de-coated over awidth b of 1 mm. This exemplary embodiment has low transmissionattenuation. However, since the de-coated region 4 with a width b of 1mm is very wide, the de-coating is visually very conspicuous anddegrades the vision through the pane 10. At the same time, the infraredreflecting action is reduced and the processing cost of the laserpatterning is significantly increased.

FIG. 10 depicts an enlarged representation of the detail Z of analternative exemplary embodiment of a pane 10 according to the inventionof FIG. 3D. In contrast to FIG. 3D, another de-coated structure 4.3 isarranged inside the inner de-coated structure 4.2. For example andwithout limiting the invention thereto, the distance b between the innerde-coated structure and the other de-coated structure 4.3 is equal tothe distance b between the outer de-coated structure 4.1 and the innerde-coated structure 4.2.

FIG. 11 depicts an enlarged representation of the detail Z of analternative exemplary embodiment of a pane 10 according to the inventionof FIG. 3D. In contrast to FIG. 3D, the outer structure 4.1 and theinner structure 4.2 are connected by a curved and, for example, inparticular a sinusoid de-coated line. Such a pane 10 has goodtransmission properties similar to those of the pane 10 of FIG. 8.Moreover, it has advantages in the de-coating using laser processing.Because of the curved course of the lines, the mirror mechanics have toexecute less large changes per time interval than with the patterning ofthe orthogonally running de-coated structures 8 of FIG. 8. The forcesacting on the mirror mechanics are lower and the laser positioning canbe executed more quickly. The patterning time is thus significantlyreduced.

FIG. 12A depicts an enlarged representation of the detail Y of analternative exemplary embodiment of a pane according to the invention 10of FIG. 3A and FIG. 12B depicts an enlarged representation of the detailZ of the pane 10 according to the invention of FIG. 12A. In thisexemplary embodiment, the regions 9 have different shapes and, forexample, the shape of a circle, of a square, and of a cross. This hasthe particular advantage that the permeability for different frequenciesand polarizations for high-frequency electromagnetic radiation can beoptimized and increased. For this, one pane 10 according to theinvention can, for example, have a large number of regions 9 withde-coated structures of various shapes and dimensions.

FIG. 13 depicts an enlarged representation of the detail Y of analternative exemplary embodiment of a pane 10 according to the inventionof FIG. 3A. The transparent, electrically conductive coating 3 hasmultiple regions 9 with cross-shaped de-coated structures 4.1,4.2.

FIG. 14 depicts an enlarged representation of the detail Z of analternative exemplary embodiment of a pane 10 according to the inventionof FIG. 3A. Another outer de-coated structure 4.3 is arranged inside theinner de-coated structure 4.2 and another inner de-coated structure 4.4is arranged inside the other outer de-coated structure 4.3. The otherde-coated structures 4.3,4.4 also have, for example, a square shape andare arranged one over another and concentrically relative to thede-coated structures 4.1,4.2. Needless to say, the other de-coatedstructures 4.3,4.4 can also have other shapes or their center can bearranged offset. The distance b₁ between the outer de-coated structure4.1 and the inner de-coated structure 4.2 is, for example, 1 mm. Thedistance b₂ between the outer de-coated structure 4.3 and the innerde-coated structure 4.4 is also, for example, 1 mm. Needless to say, thedistances b₁ and b₂ need not be the same. The length l₁ of the outerde-coated structure 4.1 is, for example, 36 mm and the length l₂ of theother de-coated structure 4.3 is, for example, 24 mm. Such a pane 10according to the invention can have improved transmission for multiplefrequency ranges, and, in this case, for two frequency ranges.

FIG. 15 depicts an enlarged representation of the detail Y of analternative exemplary embodiment of a pane 10 according to the inventionof FIG. 3A. The transparent, electrically conductive coating 3 hasmultiple regions 9 with rectangular de-coated structures 4.1,4.2. Therectangular outer de-coated structure 4.1 has a longer side length l₁ of36 mm and a shorter side length l₂ of 24 mm. This is particularlyadvantageous in order to avoid the possible interference of differentregions 9 in nested embodiments, as is depicted in FIG. 15, and toobtain improved multiband transmission.

FIG. 16A depicts a flowchart of an exemplary embodiment of the methodaccording to the invention for producing a pane 10 according to theinvention. FIG. 16B depicts a flowchart of another variant of anexemplary embodiment of the method according to the invention forproducing a pane 10 according to the invention. In contrast to FIG. 16A,in FIG. 16B, the first pane 1.1 and the second pane 1.2 are bent firstand, subsequently, the outer de-coated structures 4.1 and the innerde-coated structures 4.2 are introduced.

FIGS. 17 to 20 depict simulations of the transmission attenuation fordifferent exemplary embodiments of panes 10 according to the invention.In the simulations, analogously to the exemplary embodiment in FIG. 5, asingle glass pane 1′ with a transparent electrically conductive coating3 on the inner face IV of the single glass pane 1′ is assumed. Thetransparent, electrically conductive coating 3 has a sheet resistance of4 ohm/square. Regions 9 with de-coated structures 4.1,4.2 are arrangedinside the transparent, electrically conductive coating 3. To simplifythe simulation, an infinitely extended single glass pane 1′ withinfinitely many regions 9 was assumed.

FIG. 17 depicts a diagram of the transmission attenuation as a functionof the distance distance h between two adjacent regions 9. The regions 9contain in each case an outer de-coated structure 4.1 and an innerde-coated structure 4.2 with a square shape, as is depicted in FIG. 3D.The distance b of the outer de-coated structure 4.1 from the innerde-coated structure 4.2 was 1.5 mm. The length l of the outer de-coatedstructure 4.1 was adapted to high-frequency electromagnetic radiationwith a frequency of 1.5 GHz (GPS) and was 24 mm. The line width d of thede-coated structures was 0.1 mm. The diagram in FIG. 17 depicts thetransmission attenuation in dB as a function of the distances h betweentwo adjacent regions 9. The signal curve shows a minimal transmissionattenuation at a distance h of 4 mm. Here, the transmission attenuationis only roughly 6.3 dB compared to a single glass pane 1′ withouttransparent, electrically conductive coating 3. For distances h of lessthan 2 mm and more than 6 mm, the transmission attenuation increasessharply. For the frequency of 1.5 GHz used here, a distance b of 1.5 mmand a line width d of 0.1 mm yields a preferred region with hightransmission for distances h of 2 mm to 6 mm.

FIG. 18 depicts a diagram of the transmission attenuation as a functionof the distance distance b between the outer de-coated structure 4.1 andthe inner de-coated structure 4.2. The other parameters correspond tothose of FIG. 17. The distance h between adjacent regions 9 was 4 mm.The length l of the outer de-coated structure 4.1 was 24 mm. The linewidth d of the de-coated structures was 0.1 mm. The diagram in FIG. 18depicts the transmission attenuation in dB as a function of the distanceb. The signal curve depicts a minimal transmission attenuation at adistance b of 1.5 mm. Here, the transmission attenuation is only roughly6.3 dB compared to a single glass pane 1′ without transparent,electrically conductive coating 3. For distances b of less than 1 mm andmore than 2 mm, the transmission attenuation increases sharply. For thefrequency of 1.5 GHz used here, a distance h of 4 mm and a line width dof 0.1 mm yield a preferred region with high transmission for distancesb of 1 mm to 2.25 mm.

FIG. 19 depicts a diagram of the transmission attenuation for variousexemplary embodiments of regions 9 according to the invention withde-coated structures 4.1,4.2 as a function of frequency. The distance hbetween adjacent regions 9 was 2 mm, the distance b from the outerde-coated structure 4.1 to the inner de-coated structure 4.2 was 1 mm,and the line width d of the de-coated structures 4.1,4.2 was 0.1 mm. Theother parameters of the single glass pane 1′ and the sheet resistance ofthe transparent, electrically conductive coating 3 correspond to thoseof FIG. 17.

As Example 1, the transmission attenuation is plotted for a region 9according to the exemplary embodiment of FIG. 3D. The length l of theouter de-coated structure 4.1 is adapted to the mobile telephony bandGSM 900 and is 42 mm. The transmission attenuation for high-frequency,electromagnetic radiation of 900 MHz is roughly 7.8 dB. Mobile telephonyreception behind the pane is possible. Due to the small line width d of0.1 mm, the regions 9 with the de-coated structures 4.1,4.2 are hardlyvisible and do not interfere with vision through the pane.

As Example 2, the transmission attenuation is plotted for a region 9according to the exemplary embodiment of FIG. 8. The outer de-coatedstructure 4.1 and the inner de-coated structure 4.2 are connected oneach side of the square shape by 41 de-coated lines 8. The distancebetween two de-coated lines 8 along one side of the de-coated structures4.1,4.2 is roughly 1 mm and thus roughly 1/333-th of the wavelength λ ofthe high-frequency, electromagnetic radiation with a frequency of 900MHz. The de-coated lines 8 run orthogonal to the de-coated structures4.1,4.2. Each de-coated line 8 has, in the simulation reported, a linewidth of 0.1 mm. The transmission attenuation for high-frequency,electromagnetic radiation of 900 MHz is roughly 7.3 dB. In other words,the transmission for high-frequency, electromagnetic radiation isimproved compared to the pane 10 of Example 1. Mobile telephonyreception behind the pane is possible and improved compared toExample 1. Due to the small line width of the de-coated lines 8 of 0.1mm, the regions 9 are hardly visible and and do not interfere withvision through the pane.

FIG. 19 presents, as Comparative Example 1, the transmission attenuationfor a single glass pane 1′ with a transparent, electrically conductivecoating 3 without regions 9 with de-coated structures 4.1,4.2. Thetransmission attenuation is, at roughly 34 dB, very high such that, forexample, no mobile telephony reception is possible behind this pane.

As Comparative Example 2 according to the prior art, the transmissionattenuation is plotted for a single glass pane 1′ with a transparent,electrically conductive coating 3 that has only one square de-coatedstructure 4 with a line width d of 0.1 mm. In other words, the pane 10according to Comparative Example 2 has no inner de-coated structure 4.2or other de-coatings outside or inside the de-coated structure 4. Thetransmission attenuation is roughly 12 dB at a frequency of 900 MHz.Mobile telephony reception is impossible or possible only to a verylimited extent behind the single glass pane 1′ of Comparative Example 2.

The transmission attenuation of the Example 2 of FIG. 8 is, at afrequency of 900 MHz, lower by 4.7 dB than with the Comparative Example2 according to the prior art. This means that it was possible to reducethe transmission attenuation by a factor of 3, without the visionthrough the pane 10 and its optical properties being appreciablydegraded.

FIG. 20 depicts a diagram of the transmission attenuation for a pane 10according to the invention in accordance with FIG. 5 with regions 9 inaccordance with FIG. 14 with multiband transmission. The pane 10 has anouter de-coated structure 4.1 with an inner de-coated structure 4.2.Another outer de-coated structure 4.3 is arranged inside the innerde-coated structure 4.2 and another inner de-coated structure 4.4 isarranged inside the other outer de-coated structure 4.3. The de-coatedstructures 4.1-4.4 have a square shape and are arranged concentricallywith one another. The distance b₁ between the outer de-coated structure4.1 and the inner de-coated structure 4.2 is 1 mm, and the distance b₂between the outer de-coated structure 4.3 and the inner de-coatedstructure 4.4 is 1 mm. The length l₁ of the outer de-coated structure4.1 is 42 mm and the length l₂ of the other de-coated structure 4.3 was22 mm. The quotient of b₁/l₁ is, here, for example, 1 mm/42 mm and isthus less than ⅕. The distance h between adjacent regions 9 is 2 mm. Thesignal curve shows two minima in the transmission attenuation. The firstminimum has a transmission attenuation of 6.7 dB at 0.76 GHz. The secondminimum has a transmission attenuation of 6.7 dB at 2.3 GHz. Such a pane10 according to the invention thus has improved transmission formultiple frequency ranges and, in this example, for two frequencyranges.

FIG. 21 depicts a schematic representation of a detail of a pane 10according to the invention in plan view. One hexagonal outer de-coatedstructure 4.1 and one hexagonal inner de-coated structure 4.2 as well asanother hexagonal outer de-coated structure 4.3 and another hexagonalinner de-coated structure 4.4 are depicted. The hexagonal structures4.1-4.4 are, in each case, regular hexagons with equally long sides andare arranged concentrically with one another. Needless to say, theircenter can also be arranged offset. The distance b₁ between the outerde-coated structure 4.1 and the inner de-coated structure 4.2 is, forexample, 1.5 mm. The distance b₂ between the other outer de-coatedstructure 4.3 and the other inner de-coated structure 4.4 is also, forexample, 1.5 mm. Needless to say, the distances b₁ and b₂ need not beequal. The length l₁ of the outer de-coated structure 4.1 is, forexample, 39 mm, and the length l₂ of the other outer de-coated structure4.3 is, for example, 28 mm. The width d of the de-coated structures4.1-4.4 is also, for example, constant and is 100 μm.

The outer de-coated structure 4.1 is completely surrounded in the regionof its outer edge 14.1 and its inner edge 15.1 by the transparentelectrically conductive coating 3. Here, “outer edge” 14.1 means theregion that is situated outside the outer de-coated structure 4.1 andborders the outer de-coated structure 4.1. Accordingly, “inner edge”15.1 means the region that is situated inside the inner de-coatedstructure 4.1 and borders the inner de-coated structure 4.1. Here, theinner de-coated structure 4.2 is, for example, likewise completelysurrounded in the region of its outer edge 14.2 and its inner edge 15.2by the transparent electrically conductive coating 3. The other outerde-coated structure 4.3 and the other inner de-coated structure 4.4 arelikewise, in each case, completely surrounded in the region of theirouter edge 14.3,14.4 and their inner edge 15.3,15.4 by the transparentelectrically conductive coating 3. This means that the intermediatespaces between the outer de-coated structure 4.1 and the inner de-coatedstructure 4.2 as well as the other outer de-coated structure 4.3 and theother inner de-coated structure 4.4 are completely filled with thetransparent electrically conductive coating 3. The pane 10 according tothe invention has a section 11 with a plurality of the structures4.1-4.4 depicted here, see, for example, FIG. 2.

FIG. 22 depicts a diagram of the transmission attenuation for a pane 10according to the invention in accordance with FIG. 21 that was optimizedfor the GSM band from 820 MHz to 960 MHz as well as for the UMTS bandfrom 1700 MHz to 2200 MHz. FIG. 22 shows, as Comparative Example 1, thetransmission attenuation for a single glass pane 1′ with a transparent,electrically conductive coating 3 without regions 9 with de-coatedstructures 4.1-4.4. The transmission attenuation is, at roughly 34 dB,very high such that, for example, no mobile telephony reception ispossible behind this pane.

The transmission attenuation of the Example 3 of FIG. 21 is, at afrequency of 900 MHz, lower by 25 dB than in the Comparative Example 1according to the prior art. Moreover, the transmission attenuation ofthe Example 3 of FIG. 21 is, at a frequency of 1.9 GHz, lower by 28 dBthan in the Comparative Example 1 according to the prior art. This meansthat the transmission attenuation was reduced by a factor of 19 or by afactor of 27, respectively, without the vision through the pane 10 andits optical properties being appreciably degraded.

This result was unexpected and surprising for the person skilled in theart.

REFERENCE LIST

-   1 composite pane-   1′ single pane-   1.1 first pane,-   1.2 second pane-   2 intermediate layer-   3 transparent, electrically conductive coating-   4 de-coated region-   4.1 outer de-coated structure-   4.2 inner de-coated structure-   4.3 another outer de-coated structure-   4.4 another inner de-coated structure-   5 edge de-coating-   6 carrier film-   7 A-field of view-   8 de-coated line-   9 region-   10 pane-   11 section-   12 pane according to the prior art-   13 arrangement-   14.1,14.2,14.3,14.4 outer edge-   15.1,15.2,15.3,15.4 inner edge-   α angle-   A-A′ section line-   b, b_(h), b_(v), b₁ distance between outer de-coated structure 4.1    and inner de-coated structure 4.2-   b₂ distance between another outer de-coated structure 4.3 and    another inner de-coated structure 4.4-   d line width of a de-coated structure 4.1,4.2,4.3,4.4-   ε_(eff) effective relative permittivity-   h distance between adjacent regions 9-   l, l₁, l₂ length or width of a de-coated structure 4.1,4.2,4.3-   λ wavelength-   Y detail-   Z detail-   I outer face of the second pane 1.2-   II inner face of the second pane 1.2-   III outer face of the first pane 1.1-   IV inner face of the first pane 1.1-   V face of the intermediate layer 2-   VI face of the intermediate layer 2

We claim:
 1. A pane, comprising: at least one first pane with an outerface and an inner face, at least one transparent, electricallyconductive coating, forming a coated region that is arranged on at leastone of the outer face and the inner face of the first pane, and at leastone region with at least one outer de-coated structure and one innerde-coated structure that is formed within the coated region, wherein theouter de-coated structure and the inner de-coated structure have a sameshape, wherein a distance b between the outer de-coated structure andthe inner de-coated structure is from 0.5 mm to 30 mm and is constant,and wherein a ratio of the distance b to a length l of the at least oneouter de-coated structure, is less than or equal to ⅕, wherein thetransparent, electrically conductive coating is situated between theouter de-coated structure and the inner de-coated structure, wherein theregion between the outer de-coated structure and the inner de-coatedstructure is completely filled with the transparent, electricallyconductive coating, except at at least one region comprising a de-coatedline structure, and wherein the inner de-coated structure is completelysurrounded on its inner edge by the transparent, electrically conductivecoating.
 2. The pane according to claim 1, wherein the at least onede-coated line structure joins the outer de-coated structure to theinner de-coated structure.
 3. The pane according to claim 1, wherein theregion between the outer de-coated structure and the inner de-coatedstructure is completely filled with the transparent, electricallyconductive coating, except at regions comprising de-coated linestructures that join the outer de-coated structure to the innerde-coated structure.
 4. The pane according to claim 1, wherein thede-coated line structures are arranged orthogonal to side lines of theouter and the inner de-coated structures.
 5. The pane according to claim4, wherein a distance between two consecutive de-coated line structuresis less than one fourth of a wavelength of a transmission signal withlow attenuation through the pane.
 6. The pane according to claim 1,wherein the de-coated line structures form a single wave-shapedde-coated structure with corresponding peaks and valleys that makecontact with the outer and inner de-coated structures.
 7. The paneaccording to claim 6, wherein the single wave-shaped de-coated structureextends over the entire region between the outer de-coated structure andthe inner de-coated structure.
 8. The pane according to claim 1, whereinthe at least one region comprises 10 to 50 regions.
 9. The paneaccording to claim 8, wherein the regions are arranged horizontally. 10.The pane according to claim 8, wherein the regions are arrangedvertically.
 11. The pane according to claim 1, wherein the outerde-coated structure and the inner de-coated structure have the shape ofa square, a rectangle, a rhombus, a trapezoid, a hexagon, an octagon, across, an oval, or a circle.
 12. The pane according to claim 1, whereinthe outer de-coated structure and the inner de-coated structure have ashape with a plurality of substantially linear side line segments, andwherein a region between the outer de-coated structure and the innerde-coated structure in correspondence of at least one of the pluralityof side line segments comprises at least four de-coated line structures.13. The pane according to claim 1, wherein the outer de-coated structureand the inner de-coated structure are arranged concentrically to oneanother.
 14. The pane according to claim 1, wherein a distance of theouter de-coated structure from the inner de-coated structure is from 1mm to 5 mm.
 15. The pane according to claim 1, wherein a line width ofat least one of the outer de-coated structure and of the inner de-coatedstructure is from 25 μm to 300 μm, and wherein a line width of thede-coated line structures is substantially equal to the line width ofthe at least one of the outer de-coated structure and the innerde-coated structure.
 16. The pane according to claim 15, wherein theline width of the at least one of the outer de-coated structure and theinner de-coated structure is from 30 μm to 140 μm.
 17. The paneaccording to claim 1, wherein a minimum distance between adjacentregions of the at least one region is from 1 mm to 100 mm.
 18. The paneaccording to claim 17, wherein a minimum distance between adjacentregions is from 1 mm to 20 mm.
 19. The pane according to claim 1,wherein the at least one region has an area that has an area fraction of7% to 25% of the pane.
 20. The pane according to claim 1, wherein the atleast one first pane-contains glass, polymers, or mixtures thereof. 21.The pane according to claim 20, wherein the at least one firstpane-contains flat glass, float glass, quartz glass, borosilicate glassor soda lime glass.
 22. The pane according to claim 20, wherein the atleast one first pane-contains polyethylene, polypropylene, polycarbonateor polymethyl methacrylate.
 23. The pane according to claim 20, whereinthe at least one first pane-has an effective relative permittivityε_(eff) from 2 to
 8. 24. The pane according to claim 20, wherein the atleast one first pane-has an effective relative permittivity ε_(eff) from6 to
 8. 25. The pane according to claim 1, wherein a length of at leastone of the outer de-coated structure and the inner de-coated structureis from 10 mm to 150 mm.
 26. The pane according to claim 1, wherein thetransparent, electrically conductive coating has a sheet resistance from0.35 ohm/square to 200 ohm/square.
 27. The pane according to claim 1,wherein the transparent, electrically conductive coating has a sheetresistance from 0.6 ohm/square to 30 ohm/square.
 28. The pane accordingto claim 1, wherein the transparent, electrically conductive coatingcontains: (i) at least one metal, or (ii) at least one metal oxidelayer, or (iii) carbon nanotubes, or (iv) optically transparent,electrically conductive polymers, or (v) mixtures of at least two of (i)to (iv).
 29. The pane according to claim 28, wherein the transparent,electrically conductive coating contains silver, nickel, chromium,niobium, tin, titanium, copper, palladium, zinc, gold, cadmium,aluminum, silicon, tungsten, or alloys thereof.
 30. The pane accordingto claim 28, wherein the transparent, electrically conductive coatingcontains tin-doped indium oxide (ITO), aluminum-doped zinc oxide (AZO),fluorine-doped tin oxide (FTO, SnO₂:F), antimony-doped tin oxide (ATO,SnO₂:Sb).
 31. The pane according to claim 28, wherein the transparent,electrically conductive coating containspoly(3,4-ethylenedioxythiophenes), polystyrene sulfonate,poly(4,4-dioctyl cylopentadithiophene),2,3-dichloro-5,6-dicyano-1,4-benzoquinone, mixtures or copolymersthereof.
 32. The pane according to claim 1, wherein a length l of atleast one of the outer de-coated structure and the inner de-coatedstructure is from λ/(7*√{square root over (ε_(eff))}) to(3*λ)/(2*√{square root over (ε_(eff))}) and/or a ratio of a distance bbetween the outer de-coated structure and the inner de-coated structure,to the length l, is less than or equal to ⅕, wherein λ indicates awavelength of a transmission signal with low attenuation through thepane and ε_(eff) indicates an effective relative permittivity of thepane.
 33. A composite pane at least comprising: the pane according toclaim 1; and a second pane that is areally bonded to the pane via atleast one intermediate layer.
 34. A method, comprising: applying thepane according to claim 1 as a glazing with low transmission attenuationfor high-frequency electromagnetic radiation, in a vehicle body or in avehicle door of a means of transportation on land, on water, or in theair, in buildings as part of an external façade or of a building window,or as a built-in part in furniture and appliances.
 35. A method forproducing a pane, the method comprising: providing at least one firstpane with an outer face and an inner face; providing at least onetransparent, electrically conductive coating; applying the transparent,electrically conductive coating on the outer face or the inner face ofthe at least one first pane, thereby forming a coated region;introducing, within the coated region, at least one region with at leastone outer de-coated structure and one inner de-coated structure into theat least one transparent, electrically conductive coating, wherein adistance b between the outer de-coated structure and the inner de-coatedstructure is from 0.5 mm to 30 mm and is constant, and wherein a ratioof a distance b to a length l of the at least one outer de-coatedstructure, is less than or equal to ⅕; and introducing at least onede-coated line structure; wherein the at least one transparent,electrically conductive coating is situated between the outer de-coatedstructure and the inner de-coated structure, wherein the region betweenthe outer de-coated structure and the inner de-coated structure iscompletely filled with the transparent, electrically conductive coating,except at the at least one region of the de-coated line structure, andwherein the inner de-coated structure is completely surrounded on itsinner edge by the transparent, electrically conductive coating.
 36. Themethod for producing a pane according to claim 35, wherein the at leastone de-coated line structure joins the outer de-coated and the innerde-coated structures.
 37. The method for producing a pane according toclaim 35, comprising a step of introducing de-coated line structuresthat join the outer de-coated and the inner de-coated structures,wherein the region between the outer de-coated structure and the innerde-coated structure is completely filled with the transparent,electrically conductive coating, except at regions of the de-coated linestructures.
 38. The method for producing a pane according to claim 35,wherein the at least one outer de-coated structure and one innerde-coated structure are introduced into the at least one transparent,electrically conductive coating, by laser patterning.
 39. The method forproducing a pane according to claim 35, wherein the applying of thetransparent, electrically conductive coating, comprises: providing acarrier layer; applying the at least one transparent, electricallyconductive coating on the carrier layer; and aerially bonding thecarrier layer to the first pane.
 40. The method for producing a paneaccording to claim 39, wherein the aerially bonding the carrier layercomprises: providing an intermediate layer; and aerially bonding thecarrier layer to the first pane via the intermediate layer.